Electric dehydrator



May 15, 1923. 4 11,455,139

' F. W. HARRIIS ELECTRIC'DEHYDRATOR Fild oct; .19. 1920 2 Sheets-Sheet} rl ardwjfaigd f arieys .iF-etented May 15, 1923.

: o STATES time FORD W. HARRIS, 0]? LOS ANGELES, CALIFORNIA, ASSIGNOR TO PETROLIEUM RECTI- FYING COMPANY, OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF CALI- FOBNIA.

ELECTRIC DEHYDRATOR.

To all whom if may concern:

Be it known that I, FORD- W. HARRIS, a citizen of the United States, residing at Los Angeles, county of Los Angeles, and State of California, have invented a new and useful Improvement in Electric Dehydrators, of'which the following is a specification. 1

My invention relates to dehydrators used.

in removing water from petroleum and other oils.

It is a well known fact that if bodies of emulsion are placed between charged elecbers and with such persistency as to reduce the internal resistance of the treater to a very low value, thus reducing the volta e thereon for the limited current availab e and shutting off the dehydrating action. This, certain inventors have pro osed to prevent by agitating the materia in the treater and thus breaking these chains as fast as formed. It is often impractical to agitate the entire mass of the material in the treater to such degree as to revent this formation and it is further high y desirable that the material in the direct field should not be so agitated. i

The principal object of my invention is to provide a treater in which mechanical;

agitation is dispensed with in the active field but in which the persistence of water chains is prevented.

Further objects and advantages will be made evident hereinafter.

Fig. 1 is a cross section through a,.PI'eferred form of dehydrator embodying my invention.

Fig. 2 is a figure showing its method of application to. an oil tank.

Fig. 3 is a section on a plane indicated by the line 33 of Fig. 1.

Fig. 4 is a section through form of my invention.

- Fig. 5 is a plan view thereof.

Fig. 6 is a section of a still different form.

an alternate In the form of 'my invention illustrated in Fig. 1, I provide an outer electrode 11 which is also a container for the emulsion to be treated and an inner electrode 12. The electrode 12 is substantially a cylinder with coned ends 13 and 14. The outer electrode 11 is of such size as to tially constant arcing dlstance- A between it and the inner electrode. The outer electrode is provided with an inlet tube 15 at the top and an outlet tube 16 at the bottom. Emulsion is introduced through the ipe 17 tangentially into the inlet tube l-fi'w lnch is provided with a gas vent 18 and with a cover 19 in which an insulator 20 is placed. The insulator 20 is provided with a central rod 21 upon which the inner electrode 12 is hung. with openings 22 and 23 and with a mass of cement or sand 24 which is so distributed as to make it hang perpendicularly and equally spaced from the outer electrode 11.

An outlet pipe 30 is provided connecting' to theoutlet 16.

In practice I refer to connect the pipe 30 to a perforate "pipe 31 in the-bottom of the tank 32 and to take oil from a higher point in the tank through a pipe 33 by means of a pump 34, this oil being deliveredto the pipe 17. The rod 21 is connected through a wire 40 with one side of a secondrovide a substanary 41 of a transformer 42 and the other side of the secondary 41 bein connected by a wire 43 with the outer e ectrode 11.

'A potential of 11,000 volts is generally sufficient between the electrodes 11 and 12. The tank 32 is provided with a water outlet pipe 37.

In the operation of this embodiment of my invention. emulsion is delivered to the pipe 17 tangentially to the s ace around the insulator 20 and-at a consi erable velocity. This velocity issufliciently high to prevent chain formation over the surface of the insulator and inside the tube 15. The emul-" sion at a rapidly decreasing velocity passes downwardly over the cone 13 and slows down to a low rate of speed as it passes between the cylindrical portions of the electrodes 11 and 12. In the dehydration of oil, it is necessary that the chains as fast as formed be subjected to suflicient potential to rupture them. This potential is de endent upon the length of the chain an the average size of the particle forming the chain. It is possible to rupture'these chains if the gap is short whereas on a long 'ap, there is not suflicient potential an t ey form and persist until they short circuit the apparatus.

Inthe form of my invention illustrated in Fig. 1, the only places in which long chains chains is thereby greatly increased without danger of these chains persisting after they are formed. We have in emulsions certain average size of particle and we have a certain maximum len th for a given voltage. to whichchains may e formed with the assurance that the current density will be sufficient to rupture them afterformation. If lon r chains are formed they will persist an current will flow through them without rupturing them and in the event that a treater is provided having both lon and short distances between the charge surfaces, I have found that the chains will form through the long distance in such numbers as to ractically short-circuit the device.

have further found that bymaintaining a high velocity, I am able to almost entirely prevent the formation of chains but at the same time I greatly diminish the efiicien-cy and capacit of the ap aratus.

In-the form of ehydrator s own in Fig. 1, I prevent the long chains from forming by providing a high velocity at the points where the emulsion enters and leaves the shell 11 and at the same time I provide a slow velocity in such portions of the apparatus as have only a short gap and in which chains may be formed and disrupted with certainty. In practice, the emulsion is cir-' culated from the pipe 33 through the treater and into the pipe 31. The water tends to settle in the bottom of the tank 32 and may be withdrawn through a ipe 37. The clean oil tends to rise constant y to the top of the pipe and may be withdrawn through the pipe 35. In some kinds of oil it is desirable to pass the emulsion upwardly through the she I 11 and the direction of flow is reversed, the pump 34 being connected to the pipe 30 and the pipe 17 being connected to the pipe 31.

In Figs. 4 and 6 I show an alternate form of my invention. In the form shown in Fig. 4, a plate 60 is provided inside a casing 61 having an inlet 62 and an outlet 63. A gas vent pipe 64 is provided and emulsion is de livered tangentially through the pipe 65 around the lower portion of an insulator 66 which has a central rod 67 on which the plate 60 is secured. The emulsion enters through the ipe 65 with a whirling motion and is distri uted over the late 60, its velocity being greatly reduce in its passage thereover. The plate 60 is evenly spaced all around from the shell 61 so thatthe gap is uniform throughout. In the form of my invention illustrated in Fig. 6, two plates 60 and two containers 61 are shown connected in series.

I claim as my invention: i

1. An electric dehydrator for petroleum emulsions comprising an outer electrode; an

inner electrode supported sothat an electric field of substantiall uniform thickness is formed between sai electrodes; and means fon causing a rapid agitation of the emulsion to be treated at all oints between said electrodes having a wi or separation than the thickness of said field.

2. That step in the lart of dehydrating emulsions which comprises forming an electric field of substantially uniform thickness between charged electrodes and simultaneously agitating all portions of the emulsion between said electrodes outside said field.

3. An electric dehydrator for petroleum emulsions comprising: two electrodes between which the emulsion can pass, one electrode having every point of its active surface in contact with said emulson at a substantially uniform distance from the other electro de; means for passing said emulsion between said electrodes; and means for in,

pressin an electromotive force between said electro es.

In testimon whereof, I have hereunto set my hand at 0s Angeles, California, this 13th day of October, 1920.

FORD W. HARRIS. 

